1. Field of the Invention
This invention relates to an image composing method in an image processing system which reads out an image of characters and an image of designs drawn on a layout pasteboard (blockcopy pasteboard, rough design sheet and the like) to carry out a layout-designed output, to the method allowing a design and a screen and the like to exactly fit into the frame of the layout pasteboard to compose an output an image.
2. Description of the Prior Art
It has been heretofore desirable to provide an image processing system for typographers who require high quality printed matter in which characters, designs or the like are consolidated as a whole for editing such a system has not been proposed but would be less capable and practical in use even if it were available.
Particularly, among others, a desk top publishing art has been gradually realized in a manner of description such as a post script and the like, but is still less capable and efficient of an image art. A system for the typographers has been of course, available but is insufficient in handling (input, display, storage, processing, edition, and output and the like) data in bulk and at a high speed. This is because the data consisting of information on characters and images is too much to be synthetically processed by a description language and a central processing unit (CPU; software), thus exhibiting a poor performance. In the case of outputting only code data i.e., character code data, for manufacturing a block copy for printing, it is necessary to convert the code data to bit map data for each character and further to develop it in advance to the bit map data every some rasters. In the case of outputting only the bit map data, the whole or a part of the output image is stored in a temporary buffer and then transferred to an output unit. However, in order to reduce the capacity of the above buffer, the output unit awaits during the time when the output image is stored in the buffer.
However, the apparatus described above can not simultaneously output characters and pictures laid out and has a defect that it needs much time to realize even if the apparatus in advance carries out a layout of the character bit map in the buffer which outputs the bit map. Alternatively, the apparatus outputs the characters and the pictures on the separate paper or photographic film, respectively, and an operator patches on the paper or photographic film. Under these situations, it takes much time due to the repetition work such as exposure or printing, and photosensitive materials intermediately produced are wasted.
Further, in general, the resolution of the image recorded on a photosensitive material is much different from that of the image displayed on a CRT or the like, therefore it is necessary to carry out a coordinate transformation from a picture element coordinate on a thinned image by the logical sum operation to another picture element coordinate on an original image. In such situation, it is easy to perform the above coordinate transformation by adopting a coordinate in the vicinity of the center of the picture element on the thinned image as the coordinate to be transformed. However, in case that the thinning process is carried out by the logical sum operation, the picture element transformed may happen not to correspond to the effective picture element of the original image when the line width has more than two picture elements of the original image or the pattern is located at the corner in the thinned or rougher picture element, thus making an error happen between the frame on the layout pasteboard and the layout drawn pattern.